Titanium complex and method for producing same



UNITED STATES PATENT OFFICE.

TITANIUM COMPLEX AND METHOD FOR PRODUCING BAKE.

Specification of Letters Patent.

Patented Mar. 21, 1922.

In Drawing. Original application filed November 15, 1920, Serial No. 424,182. Divided and this application filed October 19, 1921. Serial I9 508 ,08.

To all whom it may concern:

Be it known that I, HENRY H. BUCKMAN, a resident of Jacksonville, Florida, being a citizen of the United States, have invented certain new and useful Improvements in Titanium Complexes and Methods for Producing Same, of which the following is a.

specification, this being a division of my endingI application for Letters Patent, gerial 0. 424,182, filed November 15, 1920. My present invention relates to artificial titanium complexes, i. e., materials wholly or partially composed of compounds of titanium precipitated from solutions. These complexes may consist substantially or entirely of a compound of titanium, or a mixture of compounds of titanium, o a mixture of titanium compounds and compounds of other elements. My invention has for its objects new and useful titanium complexes and methods for producing these.

I have discovered that the nature of the recipitates which may be produced by the liydrolysis of titanium salt solutions is profoundly modified by high temperaturw, and to a lesser degree'by high pressures. Upon this discovery of mine rests my present invention.

It has been well known for a long time that a weak acid solution of a titanium salt, when sufliciently dilute, could-be made to throw out a titanium complex by heating the solution. This method forms the basis of most of the laboratory and fiLCtOIiY manipulation of titanium salt solutions. t has been well known for a long time that the speed at which the hydrolysis of titanium salts takes place progresses more or less directly with the temperature, and it has been suggested many times that in order to increase the speed of these reactions, higher temperatures should be employed if possible. Higher temperatures can be utilized only by two methods, i. e., by increasing the concentration of the solution and thereby its boiling point, and by increasing the pres sure over the solution. The former method is subject to only limited application because hydrolysis of a titanium salt in solution will not take place below the boiling point of the solution after the concentration reaches a certain point. Knowing these facts, both from theoretical knowledge and practical experimental experience, I began to explore the regions of higher temperature by means of higher pressures over the solutions, i. e., by heating the solutions far above their atmospheric boiling points, in closed, gas tight containers. I believe that I am the first to have carried out such an exploration with titanium salt solutions and that I am the firs-t to have discovered and recognized that the nature of the precipitate resulting from this hydrolysis is fundamentally modified at high temperatures and pressures. Whereas at temperatures in the neighborhood of 100 degrees centigrade, the hy rolytic precipitates formed are usually slimy, and when dried are usually horny,-

tough and of little pigmenting power, on the other hand at temperatures about and above 170 degrees centigrade the same solution will yield a precipitate which is dense, and which dries to 'a smooth, fine white powder, having remarkabl pigmenting powers. I am unaware of the exact chemical composition of this new precipitate of mine, but its behaviour indicates that it is at least largely composed of some higher acid of titanium, possibly a compound in which titanium is hexavalent, not heretofore known or pr0duced,'mixed probably with other hydrolytio titanium products. Its bulk, texture, color, hiding power and general behaviour denote it as at least physically a distinct new substance not heretofore known or produced.

In addition to the new and useful pmpefi" ties of my new material, the amountof yield from a given solution at these high temperatures and pressures is very nearly double that obtained at temperatures and atmospheric pressures heretofore used.

In order to more clearl illustrate the nature of my invention and in order to more fully describe certain of its advantages, I will give one specific example of its practice, although it will be readily understood that my invention is in no way limited to or by the example given.

I'took a given quantity of a concentrated solution of titanium sulphate, carryin a small amount of free sulphuric acid. his I divided into two equal parts, and proceeded as follows :One part, I diluted with one and one half times its own volume of water and heated at 100 degrees centigrade for seven hours. At the end of that time I filtered and air-dried the precipitate. It weighed 190 grams. It was 0 a tough,

horny, translucent appearance and even when finely powdered had only a slight hiding power. Apparently it was composed chiefly of meta titanic acid. This is the method usually employed heretofore. Pursuing my new method with the other portion of the solution for comparison, I proceeded as follows :-I did not dilute the solution, but even added to its acid concentration b adding one to two per cent of its weigh in concentrated sulphuric acid. This solution I then placed in a glass-lined steel container which was made gas tight, and heated it to 185 degrees centigrade, and at the corresponding ressure for twenty minutes. I then opene the container and found that the precipitate was so bulkyand abundant that the entire contents of the container were semi-solid, and too thick to pour without the addition of water. Water was added, and the solution filtered and the precipitate washed, air-dried and weighed. t weighed 390 grams. The dried precipitate was a ure white, very smooth, dense and fine power, with remarkable hiding andpi mentlng powers, and superior to any siml ar complex known to me. I believe it to be composed substantially of a higher titanic acid, although its exact chemical composition is not known to me. That it is new and different from any titanium com lex heretofore produced is amply denote by its different physical characteristics already mentioned.

My method of heating at high tem eratures under pressure has numerous a vantages. I have discovered that by this means I can employ very much stron er acid solutions than in existing metho s, and thus prevent the precipitation of undesired impurities, notably iron. Furthermore I have discovered that'at these hi h temperatures and pressures hydrolysis wi take place in much more concentrated solutions. As mentioned above, the yield is nearl double that in methods hitherto practice Since more concentrated solutions can be used, it is unnecessary to treat such a large amount of solution this effecting a very decided economy. since stronger acid solutions can be used, the acid remaining at the end of the reaction is more concentrated and hence more valuable to recover than in the case of existi'n methods. Furthermore the time required or the hydrolysis is from one fifth to one tenth that required in methods hitherto practiced.

I have employed my novel method and produced'm new material from a variety of titanium sa ts in solution, especiall from hydrochloric acid solutions, and fin it apslicable to all titanium salts subject to hyrolysis known to me.

In my researches; I have not only carried out numerous tests and operations with the titanium solutions at high temperatures and simultaneously high pressures, but I have used high pressures and low or moderate temperatures, and I- have found as stated above that the effect of high pressure is less marked than is that of high temperature, and that combined high temperature and pressure produced the most marked effects.

I have also used my novel method to recipitate my new complex upon various ase materials, such as natural bar tes, blanc fixe, natural gypsum, calcium sulphate, ground silica, magnesia, alumina, clay, etc., rthus producing new and superior composite titamum pigments.

I have also introduced into the solution under (pressure while carrying out my novel metho dissolved substances designed to form co-plrecipitates with titanium, such as barium c loride, barium hydroxide, calcium chloride, calcium hydroxide, phosphoric acid, etc., forming thereby new and superior conllplex co-precipitates with my new mater1a I find that my new material, either alone, or when precipitated with or upon certain other substances, is excellently suited for a pigment and for mixing with oils and the like to form paints and enamels, and for the manufacture of rubber and linoleum, and for plastics and printers inks, and as a lake pigment, without first being calcined. I have also found it to work exceptionall well when mixed in paints and the like with white and read lead, lithophone, white zinc, zirconium oxide and other pigments, lending to all these its new and valuable properties of hiding and tinting wer and comparative inertness to chemical action. I have discovered that my new material and the composlte and co-precipitated products made with it and mentioned above have remarkable and superior hiding and pigmenting power when in the air-dried,uncalcined state, rendering them well suited to all the above-named purposes.

Under certain conditions in each of the above uses, however, I prefer to calcine m material, either alone or co-preci itated wit or upon other substances, and t is I do by heating in air to a dull red heat for thirty minutes.

Having now described my inventiong'what I claim as new and desire to secure by Letters Patent is the following:

1. In the production of calcined precipitates comprising titanium complexes the steps which comprise carrying out the precipitation at temperatures substantially above degrees centigrade and under pressures substantially above normal atmosphere, withdrawing the precipitate, freeing it from water, and calcining it.

2. In the production of calcined composite pigments, the steps which comprise the hydrolytic precipitation of titanium complexes on barium sulphate particles at temperatures substantially above 100 degrees centigrade and under pressures substantially above normal atmosphere, Withdrawing the composite precipitate, freeing it from water and calcining it.

3. As a new article, the hereinbefore described calcined product of the hereinbefore described uncalcined white precipitate, which precipitate comprises a titanium complex and is distinguished as consistingessentially of very fine and dense particles produced under temperatures substantially above 100 degrees centigrade and under pressures substantially above atmosphere.

4. As a new article, the hereinbefore described calcined composite pigment, the same being the calcined product of the hereinbefore described uncalcined composite product, which uncalcined composite 'product is distinguished as consisting essentially of barium sulphate particles, and adhering thereto particles of a titanium complex bydrolytically precipitated on the barium sulphate at temperatures substantially above 100 degrees centigrade and under pressures substantially above atmosphere.

HENRY H. BUCKMAN. 

